1. Field of the Invention.
This invention relates to condensation proof or fog-free mirrors and more particularly to a fog-free mirror suitable for use during normal ablution in conventional shower stalls or in standard steam baths. This invention operates through heating of its rear surface by means of a flow of the shower water or steam across its rear surface, heating that surface to the approximate temperature of the shower water or steam, and conducting heat to the front reflective surface so that said reflective surface is maintained at a temperature higher than that of the ambient, moisture laden air in the shower stall or steam bath proper, preventing condensation of that moisture on the reflective surface.
2. Description of Prior Art
Individuals often have need for use of mirrors during showers or steam baths, the most common examples of such need being males with particularly tough beards which are softened greatly by the hot water or steam and so rendered yieldable to safety razor shaving, and females with facial blemishes, or situations requiring adjustment or care best given during immersion in shower water or during steam baths. High temperatures of the moisture filled air in shower stalls or steam baths results in condensation of moisture on conventional reflective surfaces used, normally requiring that a hand held mirror have its surface frequently splashed into the shower spray, or wiped free of condensation with wash cloths and towels, while the user usually requires both hands for the operation involving said mirror.
Prevention of condensate formation on automobile windshields and special viewing windows has been achieved in a variety of ways, as noted in U.S. Pat. Nos. 1,702,877, (CLEAR VISION DEVICE FOR WINDSHIELDS) 2,059,990, (WINDSHIELD DEFROSTER) and 1,843,828, (MEANS FOR KEEPING WINDOWS, WINDSHIELDS, etc. CLEAR OF MOISTURE). U.S. Pat. No. 3,530,275, (CONDENSATION CONTROL FOR MIRRORS) a 1968 patent, provides for reflective surface heating by means of a resistive element mounted in the mirror proper and controlled by sensing of shower use through a heat sensitive switch mounted on the shower water supply line. U.S. Pat. No. 2,815,433 provides for heating a mirror's surface by means of an incandescent light bulb's radiated heat.
The device proposed herein operates on the same general principle of heating the optical surface but achieves its results in a novel and much more effective manner. In this invention, a portion of the high temperature material (viz. shower water or steam) creating the high humidity environment is directed to a manifold on the rear surface of the mirror to be acted on and is sprayed or distributed over that rear surface, heating both the rear, and, consequently, the front surface, of that mirror to the approximate temperature of the material. Since the environment of the shower stall will be cooler than the hot water being used for the shower and since steam baths are always cooler than the steam itself, the mirror's front surface will be warmer than that environment and condensation of moisture out of that environment, onto the mirror, will be positively inhibited.